/* ==========================================================================
   LEYU 赛场 — /assets/site.css
   共享外壳：reset · 变量 · 中文排版 · 头部 · 页脚 · 通用组件
   ========================================================================== */

/* ---------- reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
@media (prefers-reduced-motion: no-preference) { html { scroll-behavior: smooth; } }
body, h1, h2, h3, h4, h5, p, figure, blockquote, dl, dd, ul, ol { margin: 0; }
ul, ol { padding: 0; list-style: none; }
img, svg, video { max-width: 100%; display: block; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
a { color: inherit; text-decoration: none; }
table { border-collapse: collapse; width: 100%; }

/* ---------- tokens ---------- */
:root {
  --ink-900: #07211D;
  --ink-800: #0E2F2A;
  --ink-700: #12423B;
  --cyan-500: #2BF5C8;
  --cyan-300: #8FF3DE;
  --orange-500: #FF5A2B;
  --orange-700: #C63C14;
  --paper: #EAF7F3;
  --muted: #8AA8A1;
  --grad-a: #0A3B38;
  --grad-b: #1FD8B4;
  --warn: #FFB37A;

  --wrap: 1240px;
  --gutter: clamp(16px, 4vw, 40px);
  --r-sm: 10px;
  --r-md: 16px;
  --r-lg: 26px;
  --r-pill: 999px;
  --header-h: 74px;

  --font-body: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-num: ui-monospace, "SFMono-Regular", "JetBrains Mono", "Cascadia Mono", Consolas, "Noto Sans Mono", monospace;
  --ease: cubic-bezier(.22, .75, .24, 1);
}

/* ---------- 中文排版基础 ---------- */
body {
  background-color: var(--ink-900);
  color: var(--paper);
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.85;
  letter-spacing: .01em;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
h1, h2, h3, h4 {
  font-weight: 900;
  line-height: 1.14;
  letter-spacing: -.02em;
  font-stretch: 88%;
  color: var(--paper);
}
strong, b { font-weight: 700; color: var(--paper); }
::selection { background: rgba(43, 245, 200, .3); color: #fff; }

:focus-visible {
  outline: 2px solid var(--cyan-500);
  outline-offset: 3px;
  border-radius: 6px;
}

.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}

/* ---------- 容器 ---------- */
.shell {
  width: min(var(--wrap), calc(100% - var(--gutter) * 2));
  margin-inline: auto;
}

/* ---------- 跳过链接 ---------- */
.skip-link {
  position: fixed;
  top: 10px; left: 12px;
  z-index: 200;
  padding: 10px 18px;
  border-radius: var(--r-pill);
  background: var(--cyan-500);
  color: var(--ink-900);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .04em;
  transform: translateY(-160%);
  transition: transform .25s var(--ease);
}
.skip-link:focus-visible { transform: translateY(0); outline-offset: 4px; }

/* ==========================================================================
   头部
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 90;
  background: linear-gradient(180deg, rgba(7,33,29,.94) 0%, rgba(7,33,29,.62) 58%, rgba(7,33,29,0) 100%);
  transition: background-color .32s var(--ease), box-shadow .32s var(--ease), backdrop-filter .32s var(--ease);
}
.site-header.is-solid {
  background-color: rgba(7,33,29,.965);
  -webkit-backdrop-filter: saturate(150%) blur(12px);
  backdrop-filter: saturate(150%) blur(12px);
  box-shadow: inset 0 -1px 0 rgba(43,245,200,.18), 0 20px 44px -34px rgba(0,0,0,.95);
}

.site-header__inner {
  width: min(var(--wrap), calc(100% - var(--gutter) * 2));
  margin-inline: auto;
  height: var(--header-h);
  display: flex;
  align-items: center;
  gap: clamp(12px, 2vw, 28px);
}

/* 品牌 */
.brand {
  display: flex;
  align-items: center;
  gap: 11px;
  flex: 0 0 auto;
  min-width: 0;
  border-radius: var(--r-md);
}
.brand__mark {
  flex: 0 0 auto;
  width: 36px; height: 36px;
  border-radius: 12px;
  display: flex; flex-direction: column; justify-content: center; align-items: flex-start;
  gap: 3px;
  padding-left: 9px;
  background: linear-gradient(150deg, var(--grad-b), var(--grad-a) 72%);
  box-shadow: 0 0 0 1px rgba(43,245,200,.26), 0 10px 24px -14px rgba(43,245,200,.7);
}
.brand__mark i { display: block; height: 3px; border-radius: 2px; background: var(--ink-900); }
.brand__mark i:nth-child(1) { width: 17px; }
.brand__mark i:nth-child(2) { width: 11px; }
.brand__mark i:nth-child(3) { width: 14px; }

.brand__text { display: block; min-width: 0; }
.brand__name {
  display: block;
  font-size: 17px;
  font-weight: 900;
  letter-spacing: -.01em;
  line-height: 1.25;
  color: var(--paper);
}
.brand__tagline {
  display: block;
  font-size: 11px;
  letter-spacing: .05em;
  line-height: 1.4;
  color: var(--muted);
  white-space: nowrap;
}

/* 主导航 */
.primary-nav { flex: 1 1 auto; min-width: 0; }
.primary-nav__list { display: flex; align-items: center; gap: 2px; }
.primary-nav__link {
  display: inline-block;
  padding: 9px 13px;
  border-radius: var(--r-pill);
  font-size: 13.5px;
  letter-spacing: .03em;
  color: var(--cyan-300);
  white-space: nowrap;
  transition: background-color .2s var(--ease), color .2s var(--ease);
}
.primary-nav__link:hover { background: rgba(43,245,200,.12); color: var(--paper); }
.primary-nav__link[aria-current="page"] {
  background: var(--cyan-500);
  color: var(--ink-900);
  font-weight: 700;
  box-shadow: 0 10px 26px -16px rgba(43,245,200,.95);
}

/* 右侧操作区 */
.header-actions { display: flex; align-items: center; gap: 12px; flex: 0 0 auto; }
.live-chip {
  display: inline-flex; align-items: center; gap: 7px;
  padding: 5px 12px 5px 10px;
  border-radius: var(--r-pill);
  border: 1px solid rgba(43,245,200,.28);
  background: rgba(43,245,200,.07);
  font-family: var(--font-num);
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--cyan-300);
  text-transform: uppercase;
}
.live-chip__dot {
  width: 7px; height: 7px; border-radius: 50%;
  background: var(--orange-500);
  box-shadow: 0 0 0 0 rgba(255,90,43,.7);
  animation: live-pulse 2s infinite;
}
@keyframes live-pulse {
  0%   { box-shadow: 0 0 0 0 rgba(255,90,43,.65); }
  70%  { box-shadow: 0 0 0 9px rgba(255,90,43,0); }
  100% { box-shadow: 0 0 0 0 rgba(255,90,43,0); }
}

/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 20px;
  border-radius: var(--r-pill);
  border: 1px solid transparent;
  font-size: 13.5px;
  font-weight: 700;
  letter-spacing: .04em;
  white-space: nowrap;
  cursor: pointer;
  transition: background-color .2s var(--ease), color .2s var(--ease),
              border-color .2s var(--ease), transform .2s var(--ease);
}
.btn:active { transform: translateY(1px); }
.btn--cta {
  background: var(--orange-500);
  color: #1B0A03;
  box-shadow: 0 14px 32px -20px rgba(255,90,43,.95);
}
.btn--cta:hover { background: var(--orange-700); color: var(--paper); }
.btn--ghost {
  background: rgba(43,245,200,.10);
  border-color: rgba(43,245,200,.35);
  color: var(--cyan-300);
}
.btn--ghost:hover { background: rgba(43,245,200,.18); color: var(--paper); }
.btn--outline { border-color: var(--ink-700); color: var(--paper); }
.btn--outline:hover { border-color: var(--cyan-500); color: var(--cyan-500); }

/* 汉堡按钮 */
.nav-toggle {
  display: none;
  width: 44px; height: 44px;
  border-radius: 14px;
  border: 1px solid var(--ink-700);
  background: rgba(14,47,42,.7);
  place-items: center;
  transition: border-color .2s var(--ease), background-color .2s var(--ease);
}
.nav-toggle:hover { border-color: var(--cyan-500); }
.nav-toggle__bars { display: block; width: 20px; height: 14px; position: relative; }
.nav-toggle__bars i {
  position: absolute; left: 0; height: 2px; width: 100%;
  border-radius: 2px; background: var(--cyan-500);
  transition: transform .28s var(--ease), opacity .2s var(--ease), width .28s var(--ease);
}
.nav-toggle__bars i:nth-child(1) { top: 0; }
.nav-toggle__bars i:nth-child(2) { top: 6px; width: 70%; }
.nav-toggle__bars i:nth-child(3) { top: 12px; }
.nav-toggle[aria-expanded="true"] { border-color: var(--cyan-500); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

/* 顶部进度轨 */
.scroll-progress {
  position: absolute;
  left: 0; right: 0; bottom: 0;
  height: 2px;
  background: rgba(18,66,59,.55);
  opacity: 0;
  transition: opacity .3s var(--ease);
}
.site-header.is-solid .scroll-progress { opacity: 1; }
.scroll-progress span {
  display: block;
  height: 100%;
  width: 100%;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--cyan-500), var(--grad-b) 70%, var(--orange-500));
}

/* ==========================================================================
   页脚
   ========================================================================== */
.site-footer {
  position: relative;
  margin-top: clamp(56px, 8vw, 120px);
  padding: clamp(38px, 5vw, 68px) 0 26px;
  color: var(--paper);
  background:
    radial-gradient(120% 90% at 10% 0%, rgba(43,245,200,.10), transparent 62%),
    radial-gradient(90% 70% at 92% 10%, rgba(255,90,43,.09), transparent 64%),
    linear-gradient(180deg, var(--ink-800), var(--ink-900) 82%);
  border-top: 1px solid var(--ink-700);
}
.site-footer::before {
  content: "";
  position: absolute; top: 0; left: 0; right: 0; height: 3px;
  background: linear-gradient(90deg, var(--cyan-500), var(--grad-b) 34%, rgba(43,245,200,0) 82%);
}
.footer-rail {
  position: absolute; top: 3px; left: 0; right: 0; height: 8px;
  background: repeating-linear-gradient(90deg, rgba(43,245,200,.45) 0 24px, transparent 24px 44px);
  -webkit-mask-image: linear-gradient(90deg, #000, rgba(0,0,0,.15) 70%, transparent);
  mask-image: linear-gradient(90deg, #000, rgba(0,0,0,.15) 70%, transparent);
}
.site-footer__inner {
  width: min(var(--wrap), calc(100% - var(--gutter) * 2));
  margin-inline: auto;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr .85fr 1.15fr 1.3fr;
  gap: clamp(24px, 3vw, 48px);
  padding-bottom: clamp(26px, 3.5vw, 46px);
}

/* 品牌块 */
.footer-brand .brand { margin-bottom: 16px; }
.footer-brand__lede {
  font-size: 14px;
  color: var(--cyan-300);
  letter-spacing: .04em;
  margin-bottom: 12px;
}
.footer-brand__list { margin-bottom: 20px; }
.footer-brand__list li {
  position: relative;
  padding-left: 16px;
  font-size: 13px;
  line-height: 1.8;
  color: var(--muted);
}
.footer-brand__list li::before {
  content: "";
  position: absolute; left: 0; top: .82em;
  width: 7px; height: 2px; border-radius: 2px;
  background: var(--cyan-500);
  opacity: .8;
}
.brand--footer .brand__name { font-size: 18px; }

/* 通用栏 */
.footer-col__title {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--cyan-500);
  margin-bottom: 14px;
}
.footer-col__list { display: flex; flex-direction: column; gap: 8px; }
.footer-col__list--plain li {
  font-size: 13px;
  line-height: 1.8;
  color: var(--muted);
  display: flex;
  align-items: baseline;
  gap: 8px;
}
.footer-key {
  flex: 0 0 44px;
  font-size: 11px;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--cyan-300);
}
.footer-col--nav .footer-col__list a {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 3px 0;
  font-size: 13.5px;
  color: var(--cyan-300);
  transition: color .2s var(--ease), transform .2s var(--ease);
}
.footer-col--nav .footer-col__list a::before {
  content: "";
  width: 10px; height: 1px;
  background: var(--cyan-500);
  opacity: .55;
  transition: width .2s var(--ease), opacity .2s var(--ease);
}
.footer-col--nav .footer-col__list a:hover { color: var(--paper); transform: translateX(3px); }
.footer-col--nav .footer-col__list a:hover::before { width: 17px; opacity: 1; }
.footer-col__note {
  margin-top: 12px;
  padding-left: 12px;
  border-left: 2px solid var(--ink-700);
  font-size: 12.5px;
  line-height: 1.75;
  color: var(--muted);
}
.footer-link-more {
  display: inline-block;
  margin-top: 12px;
  font-size: 12.5px;
  letter-spacing: .04em;
  color: var(--cyan-500);
  border-bottom: 1px solid rgba(43,245,200,.35);
  transition: color .2s var(--ease), border-color .2s var(--ease);
}
.footer-link-more:hover { color: var(--paper); border-color: var(--paper); }

/* 法务条 */
.footer-legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 24px;
  padding-top: 20px;
  border-top: 1px dashed rgba(18,66,59,.95);
}
.footer-legal__copy { font-size: 12px; color: var(--muted); letter-spacing: .03em; }
.legal-links { display: flex; flex-wrap: wrap; gap: 18px; }
.legal-links a {
  font-size: 12px;
  letter-spacing: .06em;
  color: var(--cyan-300);
  transition: color .2s var(--ease);
}
.legal-links a:hover { color: var(--cyan-500); }

/* 返回顶部 */
.to-top {
  position: fixed;
  right: clamp(14px, 3vw, 28px);
  bottom: clamp(14px, 3vw, 28px);
  z-index: 70;
  width: 48px; height: 48px;
  display: grid; place-items: center;
  border-radius: var(--r-pill);
  border: 1px solid var(--ink-700);
  background: var(--ink-800);
  color: var(--cyan-500);
  font-size: 17px;
  font-weight: 700;
  box-shadow: 0 18px 40px -22px rgba(0,0,0,.95);
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity .3s var(--ease), transform .3s var(--ease),
              visibility .3s var(--ease), border-color .2s var(--ease), background-color .2s var(--ease);
}
.to-top.is-visible { opacity: 1; visibility: visible; transform: none; }
.to-top:hover { border-color: var(--cyan-500); background: var(--ink-700); }

/* ==========================================================================
   通用组件
   ========================================================================== */
.section { padding-block: clamp(44px, 6vw, 88px); }
.section__head {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 320px);
  gap: clamp(16px, 3vw, 44px);
  align-items: end;
  margin-bottom: clamp(22px, 3vw, 40px);
}
.section__eyebrow {
  display: block;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--cyan-500);
  margin-bottom: 10px;
}
.section__title { font-size: clamp(26px, 3.6vw, 46px); }
.section__lede {
  font-size: 14.5px;
  line-height: 1.9;
  color: var(--muted);
  padding-left: 14px;
  border-left: 2px solid var(--ink-700);
}

/* 网格 */
.grid { display: grid; gap: clamp(16px, 2.4vw, 28px); }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--editorial { grid-template-columns: minmax(0, 1.7fr) minmax(0, 1fr); align-items: start; }

/* 胶囊标签 */
.pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 12px;
  border-radius: var(--r-pill);
  border: 1px solid rgba(43,245,200,.28);
  background: rgba(43,245,200,.09);
  color: var(--cyan-300);
  font-size: 11.5px;
  letter-spacing: .1em;
  text-transform: uppercase;
  line-height: 1.6;
}
.pill--hot {
  border-color: rgba(255,90,43,.4);
  background: rgba(255,90,43,.14);
  color: var(--warn);
}
.pill--ghost {
  border-color: var(--ink-700);
  background: transparent;
  color: var(--muted);
}

/* 数据卡 */
.data-card {
  position: relative;
  padding: 20px 20px 18px;
  border-radius: var(--r-md);
  border: 1px solid var(--ink-700);
  border-left: 3px solid var(--cyan-500);
  background: linear-gradient(158deg, var(--ink-800), rgba(7,33,29,.92) 74%);
  overflow: hidden;
}
.data-card::after {
  content: "";
  position: absolute; right: -40px; top: -50px;
  width: 150px; height: 150px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(43,245,200,.18), transparent 68%);
  pointer-events: none;
}
.data-card__label {
  display: block;
  font-size: 11px;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 8px;
}
.data-card__value {
  display: block;
  font-family: var(--font-num);
  font-size: clamp(24px, 3vw, 34px);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -.01em;
  color: var(--cyan-500);
}
.data-card__meta { display: block; margin-top: 10px; font-size: 12.5px; color: var(--muted); }

/* 统计 */
.stat { display: flex; flex-direction: column; gap: 4px; }
.stat__value {
  font-family: var(--font-num);
  font-size: clamp(28px, 4vw, 46px);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--cyan-500);
  font-variant-numeric: tabular-nums;
}
.stat__label { font-size: 12px; letter-spacing: .12em; text-transform: uppercase; color: var(--muted); }

/* 提示条 */
.notice {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  padding: 12px 16px;
  border-radius: var(--r-sm);
  border: 1px solid rgba(255,179,122,.36);
  background: rgba(255,179,122,.08);
  color: var(--warn);
  font-size: 13.5px;
  line-height: 1.8;
}
.notice::before {
  content: "▲";
  flex: 0 0 auto;
  font-size: 10px;
  line-height: 2.4;
}

/* 斜切索引带 */
.skew-band {
  position: relative;
  overflow: hidden;
  padding: clamp(22px, 3vw, 38px) 0;
  border-radius: var(--r-lg);
  background: linear-gradient(120deg, var(--ink-700), var(--grad-a));
  transform: skewY(-6deg);
}
.skew-band__inner { transform: skewY(6deg); }

/* 图片容器 */
.media-frame {
  position: relative;
  display: block;
  overflow: hidden;
  aspect-ratio: 16 / 10;
  border-radius: var(--r-lg);
  border: 1px solid var(--ink-700);
  background: linear-gradient(152deg, var(--grad-a), var(--ink-800) 58%, var(--ink-700));
}
.media-frame > img,
.media-frame > picture > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}
.media-frame::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(43,245,200,.10) 1px, transparent 1px),
    linear-gradient(90deg, rgba(43,245,200,.10) 1px, transparent 1px);
  background-size: 44px 44px;
  -webkit-mask-image: linear-gradient(160deg, #000, transparent 72%);
  mask-image: linear-gradient(160deg, #000, transparent 72%);
}
.media-frame--wide { aspect-ratio: 21 / 9; }
.media-frame--tall { aspect-ratio: 4 / 5; }
.media-frame--square { aspect-ratio: 1 / 1; }
.media-frame__caption {
  position: absolute;
  left: 16px; right: 16px; bottom: 14px;
  font-size: 12.5px;
  letter-spacing: .04em;
  color: var(--cyan-300);
  text-shadow: 0 1px 14px rgba(0,0,0,.8);
}

/* 面包屑 */
.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 11.5px;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 18px;
}
.breadcrumbs li { display: inline-flex; align-items: center; gap: 8px; }
.breadcrumbs li + li::before { content: "/"; color: var(--ink-700); }
.breadcrumbs a { color: var(--cyan-300); transition: color .2s var(--ease); }
.breadcrumbs a:hover { color: var(--cyan-500); }

/* 正文 */
.prose { max-width: 70ch; font-size: 15px; line-height: 1.9; color: #D3EAE3; }
.prose > * + * { margin-top: 16px; }
.prose h2 { font-size: clamp(22px, 2.6vw, 30px); margin-top: 40px; }
.prose h3 { font-size: clamp(18px, 2vw, 22px); margin-top: 28px; }
.prose ul, .prose ol { padding-left: 20px; list-style: disc; }
.prose ol { list-style: decimal; }
.prose li { margin-top: 6px; }
.prose a {
  color: var(--cyan-300);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-color: rgba(143,243,222,.45);
}
.prose a:hover { color: var(--cyan-500); }
.prose strong { color: var(--paper); }

/* 章节目录 */
.toc { border-left: 2px solid var(--ink-700); }
.toc__list { margin-left: -2px; display: flex; flex-direction: column; }
.toc a {
  display: block;
  padding: 7px 0 7px 14px;
  border-left: 2px solid transparent;
  font-size: 13.5px;
  color: var(--muted);
  transition: color .2s var(--ease), border-color .2s var(--ease), padding-left .2s var(--ease);
}
.toc a:hover { color: var(--cyan-300); padding-left: 18px; }
.toc a[aria-current="true"] { color: var(--cyan-500); border-left-color: var(--cyan-500); font-weight: 700; }

/* 显现动效 */
.js [data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity .6s var(--ease), transform .6s var(--ease);
}
.js [data-reveal].is-in { opacity: 1; transform: none; }

/* ==========================================================================
   响应式
   ========================================================================== */
@media (max-width: 1200px) {
  .live-chip { display: none; }
}
@media (max-width: 1120px) {
  .primary-nav__link { padding: 8px 10px; font-size: 13px; }
}
@media (max-width: 1040px) {
  :root { --header-h: 64px; }
  .nav-toggle { display: grid; }

  .primary-nav {
    position: fixed;
    left: 0; right: 0;
    top: var(--header-h);
    max-height: calc(100dvh - var(--header-h));
    overflow-y: auto;
    padding: 14px var(--gutter) 30px;
    background: linear-gradient(180deg, var(--ink-800), var(--ink-900));
    border-bottom: 1px solid var(--ink-700);
    box-shadow: 0 34px 60px -34px rgba(0,0,0,.95);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-14px);
    pointer-events: none;
    transition: opacity .28s var(--ease), transform .28s var(--ease), visibility .28s var(--ease);
  }
  .primary-nav[data-open="true"] {
    opacity: 1;
    visibility: visible;
    transform: none;
    pointer-events: auto;
  }
  .primary-nav__list { flex-direction: column; align-items: stretch; gap: 6px; }
  .primary-nav__link {
    display: block;
    padding: 13px 16px;
    border-radius: 14px;
    font-size: 15px;
    background: rgba(43,245,200,.05);
  }
  .primary-nav__link[aria-current="page"] { background: var(--cyan-500); }
  .brand__tagline { display: none; }
}
@media (max-width: 1000px) {
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .section__head { grid-template-columns: minmax(0, 1fr); align-items: start; }
  .grid--editorial { grid-template-columns: minmax(0, 1fr); }
}
@media (max-width: 880px) {
  .grid--3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 720px) {
  body { font-size: 14px; }
  .grid--2, .grid--3 { grid-template-columns: minmax(0, 1fr); }
  .skew-band { transform: none; border-radius: var(--r-md); }
  .skew-band__inner { transform: none; }
  .footer-grid { grid-template-columns: minmax(0, 1fr); gap: 28px; }
  .footer-legal { flex-direction: column; align-items: flex-start; }
  .to-top { width: 44px; height: 44px; }
}
@media (max-width: 560px) {
  .brand__mark { width: 32px; height: 32px; border-radius: 10px; padding-left: 8px; }
  .brand__mark i:nth-child(1) { width: 15px; }
  .brand__mark i:nth-child(3) { width: 12px; }
  .brand__name { font-size: 15px; }
  .header-actions { gap: 8px; }
  .header-cta { padding: 9px 14px; font-size: 12.5px; letter-spacing: .02em; }
  .nav-toggle { width: 40px; height: 40px; }
  .footer-key { flex-basis: 100%; }
  .footer-col__list--plain li { flex-direction: column; gap: 2px; }
}

/* ==========================================================================
   可访问性：减少动态
   ========================================================================== */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    scroll-behavior: auto !important;
  }
  .js [data-reveal] { opacity: 1; transform: none; }
  .live-chip__dot { animation: none; box-shadow: none; background: var(--orange-500); }
  .to-top { transform: none; }
}